R448A, which is a quinary mixture and has a global warming potential (GWP) of 1390, and R449A, which is a quaternary mixture and has a GWP of 1282, have been recommended for commercial refrigeration systems to replace R404A, which has a GWP of 3943 as per EU Regulation No. 517/2014. The thermodynamic properties of R448A and R449A, such as vapor pressure, saturated density, and vapor-liquid coexistence curve with critical points were computed for temperatures ranging from 233.15 K to 343.15 K via molecular dynamics (MD) simulations. The computed vapor pressures of R448A and R449A closely match that of R404A. The MD simulations predict the saturated densities of R448A and R449A very well in the subcritical region. The computed critical points of the three blend refrigerants were compared with published data. The radial distribution functions (RDFs) show that intra-molecular and inter-molecular interactions occur in the vapor and liquid phases for R448A and R449A. The thermodynamic properties of R448A and R449A estimated in this work will be useful for analyzing the performance of commercial refrigeration systems operating with these new blend refrigerants.

中文翻译：

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使用分子动力学模拟计算 R448A 和 R449A 在 233.15 K 至 343.15 K 饱和温度范围内的热力学性质


R448A（五元混合物，全球变暖潜值 (GWP) 为 1390）和 R449A（四元混合物，GWP 为 1282）已被推荐用于商业制冷系统，以取代 R404A（GWP 为3943 根据欧盟法规第 517/2014 号。通过分子动力学 (MD) 模拟，计算了 233.15 K 至 343.15 K 温度范围内 R448A 和 R449A 的热力学性质，例如蒸气压、饱和密度和具有临界点的气液共存曲线。 R448A 和 R449A 的计算蒸气压与 R404A 的蒸气压非常接近。 MD 模拟很好地预测了 R448A 和 R449A 在亚临界区域的饱和密度。将计算出的三种混合制冷剂的临界点与已发表的数据进行了比较。径向分布函数 (RDF) 显示 R448A 和 R449A 的气相和液相中发生分子内和分子间相互作用。这项工作中估计的 R448A 和 R449A 的热力学特性将有助于分析使用这些新型混合制冷剂运行的商用制冷系统的性能。